O-(4-nitrophenyl) alkanephosphonic chlorides



Patented Feb. 9, 1954 UNITED STATES PATENT OFFICE O- 4-NITROPHENYL) ALKANEPHOSPHONIC CHLORIDES Henry Tolkmith, Midland, Mich, asslgnor to The Dow Chemical Company, Midland, Mich, a corporation of Delaware No Drawing. Application c l-i121, 1953, Serial No. 350,230

3 Claims.

The present invention is directed to the O- (4-nitrophenyl) alkanephosphonic chlorides of the formula in an inert organic solvent such as benzene or diethyl ether. The reaction is carried out in the presence of a hydrogen chloride acceptor such as pyridine.

In carrying out the reaction the 4-nitrcphenol and hydrogen chloride acceptor are dispersed in the solvent and the resulting mixture added portionwise with stirring to the alkanephosphonic dichloride dispersed in the same solvent. The mixture is thereafter heated for a period of time at a temperature of from 35 to 80 C. to complete the reaction. The reaction takes place smoothly at the temperature range of from to 80 C. and at a rate which varies directly with the employed temperature. The reaction is somewhat exothermic, temperature being controlled by regulation of the rate of contacting the reactants and by the addition and subtraction of heat, if required. Upon completion of the reaction, the mixture may be filtered and the filtrate distilled under reduced pressure at gradually increasing temperatures to separate low boiling constituents and to obtain as a residue the desired O-(4-nitrophenyl) alkanephosphonic chloride. Distillation temperatures substantially in excess of 150 C. for any appreciable period of time should not be employed as the desired product has a tendency to decompose at such temperature.

In an alternative method, the new compounds may be prepared by reacting one molecular proportion of an alkali metal'4-nitrophenolate with one molecular proportion of the alkanephos-v phonic dichloride in an inert solvent such as benzene. Or the alkali metal phenolates found useful in the reaction, it is preferred to employ the sodium compound. In carrying out the reaction, the sodium phenolate is added portionwise to the alkanephosphonic dichloride dispersed in the solvent and the resulting mixture heated for a period of time at a temperature of from 30 to C. to complete the reaction. In practice it is sometimes convenient to operate at the boiling temperature of the reaction mixture and under reflux. The conditions of reaction and methods of separation are essentially as previously described.

Example 1.-O-(4nit70phe'nyl) phonic chloride C Hs-P 120.5 grams (0.865 mole) of 4-nitrophenol and 76 grams (0.96 mole) of pyridine were dispersed in 1200 milliliters of diethyl ether and the resulting mixture added portionwise with stirring to 350 grams (2.63 moles) of methane phosphonic dichloride (boiling at 163 C. at atmospheric pressure) dispersed in milliliters of diethyl ether. The resulting mixture was thereafter heated for one hour at the boiling temperature and under reflux to complete the reaction. At the end of this period, the mixture was filtered and the filtrate distilled under reduced pressure to a temperature up to 110 C. to obtain as a residue O-(4-nitrophenyl) methane-phosphonic chloride. The latter is a viscous oil having a density or 1.4490 at 20 C.

Example 2.-O-(4-nitropheniul) ethanephosphonic chloride 0 Olga. II

34.5 grams (0.248 mole) of 4-nitr0phen0l and 22 grams (0.278 mole) of pyridine were dispersed in 350 milliliters of diethyl ether and the resulting mixture added portionwise with stirring to '71 grams (0.483 mole) of ethanephosphonic dichloride (boiling at C. at atmospheric pressure) dispersed in 50 milliliters of diethyl ether. The resulting mixture was thereafter heated for 2 hours at the boiling temperature and under reflux to complete the reaction. At the end of this period, the reaction mixture was filtered and methanephos- 3 the filtrate distilled under reduced pressure to a temperature up to 110 C. to obtain as a residue 0 (4 nitrophenyl) ethanephosphonic chloride. This compound is a viscous oil having a density of 1.4107 at 20 C.

The new O-(4-nitrophenyl) alkane-phosphonic chloride products are effective as parasiticides and adapted to be employed for the control of a wide range of agricultural and household pests- For such use, the eompounds may be In representative operations against flies and cockroaches, 100 percent kills of these pests are obtained with dust compositions containing 4.5 percent by Weight of the toxic alkanephosphonic chlorides.

This is a continuation-in-part of my copending application Serial No. 203,758, filed December 30,1950. 'I claim:

1. O-(4-nitrophenyl) alkanephosphonic chlo ride of the formula wherein R represents a member of the group or in water dispersion with or without the adconsisting of methyl and ethyl.

O (4-nitrophenyl) methanephosphonic chlon e.

3. O l-nitrophenyl) ethanephosphonic chloride. HENRY TOLKMITH; It.

No references cited. 

1. O-(4-NITROPHENYL) ALKANEPHOSPHONIC CHLORIDE OF THE FORMULA 